Trip to the National Museum of the US Air Force

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The Cargo Master first flew in 1956 for the Military Air Transport Service. It was able to carry a wide variety of cargo including ballistic missiles. They were withdrawn from service in 1971 and replaced by the C-5A Galaxy

 
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Actually not true. The wrinkles on the skin, as can be seen, are approximately at a 45 degree angle. They are sheer stress lines associated with the fuselage monocoque engineering design, wherein the wings and wing box would torque the fuselage with sheer stress. Imagine a huge structure that flexes. The wings and ailerons force mid-fuselage torque and the forward and aft fuselage must reluctantly also turn (torque) in the same direction. The delay results in sheer stress on the fuselage skin seen as the 45 degree "wrinkles".
 
So, Matt, if it's sitting on it's landing gear, what would be torquing the fuselage? I did my university thesis on shear in concrete panels and I agree with you that shear is causing the 45 degree pattern but I can't get my head around why it would be torque. The wrinkles are also visible on the B-36 tail so I just don't get the torque thing.
 

I'm not going to guess on the B-36. I too noticed that there were many wrinkles on other "non-B52" structures like the leading edge of the vertical stabilizer that I can't fathom their origin. I can't comment intelligently upon them. However, with respect to the Boeing structural designs, my engineering background addressed these specifically. The skin wrinkles are not a static display of "torque". Rather they are remenants of the torque forces that I described above. Imagine the forces of the wing/ailerons applying torque to a fuselage (tube) mid- structure. That then results in sheer forces manifesting themselves as 45 degree angle creases/wrinkles on the fuselage (tube) both fore and aft.

Use a paper towel roll. Twist the $hit out of it and you will see the same forces manifest themselves in the paper towel roll.

Science rules!
 
Matt, my statement was based on my memory of that article I read some 30 years ago and not any first hand knowledge, but as I think about it now I, like Andy, am having a hard time getting my mind around the torque thing. I also have experience with sher stress failures in concrete structures (mostly first hand experience as opposed to schooling) and it would seem to me that a torquing of the fuselage would put opposite angles of wrinkles on each side of the fuselage, for instance low front to high back on one side and high front to low back on the other. (I tried out your paper towel roll suggestion and confirmed it) The B-52s all seem to have low forward to high rear wrinkles on both sides of the fuselage which with my construction experience seems to fit with that old article to indicate sagging of the fuselage forward of the wing/forward landing gear. But of course I have no experience in aircraft structures. Just trying get my mind around it using common sense, which could be dead wrong.
 
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Back to the pictures

The EC-121 was a radar-picket version of the C-121 passenger plane which was in turn a military version of the Constellation civil airliner. They saw service with the Air Defense Command flying patrols off the U.S. coasts as part of the Distant Early Warning (DEW) Line. The EC-121s remained in service until they were replaced by the E-3 AWACS.

 
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More excellent material Glenn, this is some interesting stuff. And Matt, if you are looking at the B-52 from the left side for instance, in reference to the torque you are speaking of. Is the main wing structure trying to rotate, front edge up? This, and I could be way off, if my theory is close would be pulling back on the top of the airframe and pulling forward on the rear section along the top of the fuselage. Am I anywhere close?
 
Messy1 said:
Hanging above the Constellation in the first picture, isn't that one of the Mig's from Top Gun if I'm not mistaken?
Click to expand...
Very good eye! Its an F-5, and they were used as MiGs in Top Gun. That one was rather hard to get a decent picture of but I think I got one of the bottom which I'll get to when I get into the more modern fighters which will be coming up soon.
 
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